This invention relates to surgical retractors generally of the type that include a rack and pinion operated pair of retractors for opening a region of the body, often the chest cavity, to provide access for performing surgery and to methods of performing such surgery.
Surgery for the correction of congenital defects in infants is a well-known but difficult procedure. Coarctation of the aorta, an abnormal narrowing which may severely inhibit blood circulation, especially in infants, may require surgical correction. It is, of course, important to provide adequate exposure of the aorta in this type of surgery with minimum trauma to the patient.
Similarly, correction of congenital defects in the heart per se requires adequate exposure of the heart chambers with minimum trauma.
Traditional retraction methods and retractors are generally unsuitable for these procedures. The heart or aorta are often exposed using a muscle sparing operation.
In repairs of congenital defects of the aorta, the infant or child is placed laying on the right side. An incision is made in the left lateral portion of the upper thorax, such that the incision follows the edges of the muscles, rather than across the muscles. The present practice is to use a first retractor to retract the muscles, then to use a second retractor, placed at right angles to the first retractor and on top of the first retractor to spread the ribs, thus exposing the pleural cavity.
In general, the typical retractor consists of two sternal blades attached, respectively, to a pair of arms. One arm is rigidly attached to a rack containing a single row of gear teeth, and the second arm rigidly fixed to a moving member that is able to slide along the rack. A rotatable handle, hinged to a simple cog gear is contained in the moving member and engages the rack. Rotation of the handle caused the member to move along the rack, thus changing the separation distance between the sternal blades.
In general, prior art retractors spread a surgical opening in only one direction. It is desirable in some instances, especially in pediatric cardiac surgery to be able to retract the same or different layers of muscle or bone structure, e. g. ribs, in different directions to make the surgical area more accessible.
Devices are known in which an incision in tissue is opened in more than one direction, e.g. providing a generally circular orifice. Such devices are described, for example, in U.S. Pat. Nos. 6,042,596 to Bonutti; 6,162,172 to Cosgrove et. al.; and 6,159,201 to Hamilton, et. al. However, devices such as those referred to and other known prior art devices are not useable in surgical procedure for correcting cardiac or aortic congenital defects in infants or children.
It is an object of this invention to provide a retractor that conforms more readily to the anatomy of the patient and to permit retraction of the muscles of an infant in one direction and retraction of ribs in a perpendicular direction to render a surgical site, e.g. the heart or aorta, accessible. The invention may, of course, be used on adults or even on animals in veterinarian practice but it has unique and special applicability to surgery on infants and young children.
The present invention is, in one embodiment, a surgical retractor that is configured and constructed to be conformable to the chest or other anatomical structure of a patient comprising means for retracting soft tissue or bone structure in two relative generally perpendicular directions.
Preferably it is configured and constructed to be conformable to the chest or other anatomical structure of a patient comprising means for retracting soft tissue or bone structure in two relative generally perpendicular directions and comprises first and second spaced retractor plates each having first and second ends, third and fourth retractor plates hingably connected respectively to the first ends and to the second ends of the first and second spaced retractor plates for angular movement relative to said first and second spaced retractor plates, and a rack and pinion retractor blade assembly mounted on each of the respective retractor plates. The retractor device is constructed and configured to permit reciprocal movement of generally opposed first and second retractor blades and to permitting reciprocal movement of generally opposed third and fourth retractor blades, the direction of reciprocal movement of the third and fourth retractor blades being generally perpendicular to the direction of reciprocal movement of the first and second retractor blades.
In a preferred embodiment, the first and second retractor plates are generally planar and lie generally in the same plane and further comprise means for locking one or both of the third and fourth retractor plates at selected angles of up to about 45xc2x0 in either direction relative to the plane of the first and second retractor plates.
Preferably, at least two of the blades, and optionally all of the blades, are configured and constructed to define arcuately curved tissue engaging structure.
The tissue engaging structure of the first and second retractor blades may be longer than the tissue engaging structure of the third and fourth retractor blades or, depending on the order used to identify the blades, the tissue engaging structure of the third and fourth retractor blades may be longer than the tissue engaging structure of the first and second retractor blades.
It is preferred that the first and second spaced retractor plates each have first and second ends, the third and fourth retractor plates are hingably connected respectively to the first ends and to the second ends of the first and second spaced retractor plates for angular movement relative to said first and second spaced retractor plates; and a rack and pinion retractor blade assembly is mounted on each of the respective retractor plates, the retractor device being constructed and configured to permit reciprocal movement of generally opposed first and second retractor blades and to permitting reciprocal movement of generally opposed third and fourth retractor blades, the direction of reciprocal movement of the third and fourth retractor blades being generally perpendicular to the direction of reciprocal movement of the first and second retractor blades. It is also preferred that the retractor mechanism be constructed and configured such that the first and second retractor plates are generally planar and lie generally in the same plane and further comprising means for locking one or both of the third and fourth retractor plates at selected angles of 0 degrees and angles of up to about 45xc2x0 relative to the plane in which the first and second retractor plates lie. Optionally, the tissue engaging structure of the first and second retractor blades may longer than the tissue engaging structure of the third and fourth retractor blades.
In another embodiment, the invention is embodied in a method of performing surgery upon infants and children to correct defects of the heart or aorta and related tissue, comprising making an incision in the left lateral portion of the upper thorax, such that the incision follows the edges of the muscles, placing a single retractor mechanism over the incision, said retractor mechanism comprising means for retracting soft tissue in one direction and retracting bone structure in a generally perpendicular direction, retracting soft tissue in a first direction, and retracting rib tissue in a second direction generally perpendicular to the first direction.
The inventive concept also includes the method of performing surgery to correct defects of the heart and related tissue comprising making a minimal skin incision over the sternum, placing a single retractor mechanism over the incision, said retractor mechanism comprising means for retracting skin and underlying soft tissue in one direction and retracting bone structure in a generally perpendicular direction, using said mechanism to retract skin and soft tissue in a first direction, making an incision through the sternum or a portion of the sternum, and using the mechanism to retract the sternal bone in a second generally direction, the second direction being generally perpendicular to the first direction.
The method of may include the use of the structures and alternatives described above and in more detail hereinafter.